Category Archives: plasticity

Norman Doidge’s book, The Brain that Changes Itself (Penguin, 427pp. ($18)), was published in 2007, now some twelve years ago. This publication occurred towards

Cover Art: The Brain That Changes Itself by Norman Doidge

the beginning of the era of neuro-hype that now has us choking on everything from neuroaesthetics to neurohistory, from neuromarketing to neurozoology. So pardon my initial skepticism.

However, this book is the real deal. To those suffering from a variety of neurological disorders or issues, extending from major strokes to learning disabilities or emotional disorders, Doidge’s narratives offer hope that hard work pays off. If more authors and editors would have read (and understood!) it, today’s neuro-hype would be a lot less hyped.

Let me explain. There is neural science aplenty in Doidge’s exposition and defense of the flexibility – key term: plasticity – of the brain. There are also plentiful high tech devices (prostheses) that make for near science fiction innovation, except that they are engineering interventions, not fictions.

However, what distinguishes Norman Doidge’s contribution is that, in every case without exception, the neural science “breakthrough” on the part of the patient is preceded by substantial – in some cases a year or more – of hard work on the patient’s behalf to regain lost neural functionality.

Yes, from the point of view of our everyday expectations of what can be attained in six weeks of twice a week rehabilitation, the results are “miraculous”; but upon closer inspection the “miracle” turns out to be 99% perspiration and 1% inspiration.

I hasten to add that the exact distribution of effort varies. But the point is that, while the “miraculous” is supposed to be uncaused, lots of hard work on the part of the patient, properly directed, is a key determining factor. This in no way detracts from the authentic innovations and corresponding effort on the part of the neural scientists and engineers engaging in the rehabilitation process.

The woman who lost her sense of balance tells of a woman (Cheryl) whose ability to orient herself in space is “taken out” by an allergic reaction to an antibiotic (gentamicin) administered to treat an unrelated condition. Balance is sometimes considered a sixth sense, for without it the person literally looses her balance and falls over. Thus, Cheryl became the woman perpetually falling. She becomes a “Wobbler.”

While such a condition does not cause a person to die, unless the fall proves fatal, but it destroys the ability to engage in the activities of daily living. Enter Paul Bach-y-Rita, MD, and Yuri Danilov (biophysicist) (p. 3), who design a helmet that transmits orientation data to Cheryl through an ingenious interface that she can hold on her tongue like a small tongue depressor. It transmits a tingling sensation towards the front of the stick if she is bending forward, towards the back of the stick if she is bending backwards, and so on. Who would have thought it? Turns out that the tongue is a powerful brain-machine interface.

After some basic training as Cheryl wore it, she was able to orient herself and not fall over. After awhile, she took the helmet off and found that the ability to orient herself lasted a few minutes. There was a residual effect. With more training, the persistence of the after effect was extended. Finally, after a year of work, she was able to dispense with the helmet. She had “magically” regained her sense of balance. The neural circuits that had been damaged were in effect by-passed and the functionality taken over by other neural areas in the brain based on the training. Cheryl was no longer a Wobbler.

This is the prelude to the narrative of the dramatic recovery of Bach-y-Rita’s own father, the Catalan poet Pedro Bach-y-Rita, who has a massive disabling stroke, leaving him paralyzed in half his body and unable to speak.

After four weeks of rehabilitation based on pessimistic theories that the brain could not benefit from extended treatment, the father, Pedro, was literally a basket case. Enter brother George – Pedro’s other son. Now George did not know that rehab was supposed to be impossible, and took the father home to the house in Mexico. They got knee pads and taught him to crawl – because it is useful to crawl before one walks, which Pedro eventually did again after a year of effort. Speech and writing also returned after much effort copying and practicing phonetics.

Pedro returned to teaching full time at City College in New York (p. 22) until he retires years later. After Pedro’s death, a routine autopsy of his brain in 1965, showed “that my father [Pedro] had had a huge lesion from his stroke and that it had never healed, even though he recovered all these functions” (p. 23).

The take-away? What modern neural science means when it asserts that nerve cells do not heal is accurate. But “plasticity” means that the brain is able to produce alternative means of performing the same messaging and functional activity. “The bridge is out,” so plasticity invents a detour around the damaged area. Pedro walks and talks again and returns to teaching.

Conventional rehab usually lasts for an hour and sessions are three times a week for (say) six weeks. Edward Taub has patients drill six hours a day, for ten to fifteen days straight. Patients do ten to twelve tasks a day, repeating each task ten times apiece. 80 percent of stroke patients who have lost arm functionality improve substantially (p. 147). Research indicates the same results may be available with only three hours a day of dedicated work.

In short, thanks to plasticity, recovery from debilitating strokes is possible but – how shall I put it delicately? – it is not for the faint of heart. Turn off the TV! Get out your knee pads?

So when doctors or patients say that the damage is permanent or cannot be reversed, what they are really saying is that they lack the resources to support the substantial but doable effort to retrain the brain to relearn the function in question – and are unwilling to do the work. The question for the patients is: How hard are you willing to work?

The next case opens the diverse world of learning disabilities. Barbara Arrowsmith looms large, who as a child had a confusing set of learning disabilities in spatial relationships, speaking, writing, and symbolization. Still, she had a demonstrable talent for reading social clues. She was not autistic, but seemingly “retarded” – cognitively impaired. She had problems with symbolic relationships, including telling time.

With the accepting and tolerant environment provided by her parents, who seemed really not to “get” what was going on, Barbara set about to cure herself. She (and her parents) invented a series of exercises for herself that look a lot like what “old style” school used to be: A lot of repetitive exercises, rote memorization, copying, and structure. Flash cards to learn how to tell time. There is nothing wrong with the Montessori-inspired method of letting the inner child blossom at her or his own rapid rate of learning, except it does not work for some kids. Plasticity demonstrates that “one size fits all” definitely does notfit all.

The result? The Arrowsmith School was born, featuring a return to a “classical” approach:

“[…] [A] classical education often included rote memorization of long poems in foreign languages which strengthen the auditory memory […] and an almost fanatical attention to handwriting, which probably helped strengthen motor capacities […] add[ing] speed and fluency to reading and speaking” (pp. 41–42).

This also provides the opportunity to take a swipe at “the omnipresent PowerPoint presentation – the ultimate compensation for a weak premotor cortex.” Well said.

Without having anything wrong with their learning capabilities as such, some children have auditory cortex neurons that are firing too slowly. They could not distinguish between two similar sounds – e.g., “ba” and “da” – or which sound was first and which second if the sounds occurred close together (p. 69):

“Normally neurons, after they have processed a sound, are ready to fire again after about a 30-millesecond rest. Eighty percent of language-impaired children took at least three times that length, so that they lost large amounts of language information” (p. 69).

The solution? Exploit brain plasticity to promote the proliferation of aural dendrites that distinguish relevant sounds and sounds, in effect speeding up processing by making the most efficient use of available resources.

Actually, the “solution” looks like a computer game with flying cows and brown bears making phonetically relevant noises. Seems to work. Paula Tallal, Bill Jenkins, and Michael Merzenich get honorable mentions, and their remarkable results were published in the journal Science(January 1996). Impressive.

Though not developed to treat autism spectrum disorders, such exercises have given a boost to children whose sensory processing left them over-stimulated – and over-whelmed, resulting in withdrawal and isolation. Improved results with school work – the major “job” of most children – leads, at least indirectly, to improved socialization, recognition by peers and family, and integration into the community (p.75). Once again, it seems to work.

As a psychoanalytically trained medical doctor, one of Doidge’s interests is in addiction in its diverse forms, including alcohol and Internet pornography. For example, Doidge approvingly quotes Eric Nestler, University of Texas, for showing “how addictions cause permanent changes in the brains of animals” (p. 107). This comes right after quoting Alcoholics Anonymous that there are “no former addicts” (p. 106). Of course, the latter might just be rhetoric – “don’t let your guard down!” Since this is not a softball review, I note that “permanent changes in the dopamine system” are definitely notplasticity. A counter-example to Doidge’s?

A conversation for possibility – that is, talk therapy – which evokes the issues most salient to being human – relationships, work, tastes, and loves – activate BNGF [brain-derived neural growth factor], leading to a proliferation or pruning back of neural connections. This is perhaps the point to quote another interesting factoid: “Rats given Prozac [the famous antidepressant fluoxatine] for three weeks had a 70 percent increase in the number of cells in their hippocampus” [the brain area hypothesized to be responsible for memory translation in humans] (p. 241). This is all good news, especially for the rats (who unfortunately did not survive the experiment), but the devil, as usual, is in the details.

On a positive note, Freud was a trained neurologist, though he always craved recognition from the psychiatric establishment [heavens knows why – perhaps to build his practice]. In a separate chapter including a psychoanalytic case (“On Turning Our Ghosts into Ancestors,” an unacknowledged sound byte from Hans Loewald, psychoanalyst), Doidge’s points out in a footnote that having a conversation with a therapist changes one’s neurons too. The evidence is provided by fMRI studies before and after therapy (p. 379). This is the real possibility for – get ready, welcome to – neuropsychoanalysis.

Like most addictions – alcohol, street drugs, gambling, cutting – Internet porn is a semi-self-defeating way of regulating one’s [dis-regulated] emotions. The disregulated individual may usefully learn expanded ways of regulating his emotions, including how to use empathy with other people to do so. Meanwhile, the plasticity of addictive behavior turns out to be more sticky and less flexible than the optimistic neuro-plasticians (if I may coin a term) might have hoped.

Doidge has an unconventional, but plausible, hypothesis that “we have two separate pleasure systems in our brains, one that has to do with exciting pleasure and one with satisfying pleasure” (p. 108). Dopamine versus endorphins? Quite possibly. Yet one doesn’t need neuropsychoanalysis to appreciate this.

Plato’s dialogue Gorgias makes the same point quite well (my point, not Doidge’s). Satisfying one’s appetites puts one in the hamster’s wheel of endless spinning whereas attaining an emotional-cognitive balance through human relations, contemplation, meditation, or similar stress reducing activities provide enduring satisfaction. The tyrant may be able to steal your stuff – your property, freedom, and even your life – but the tyrant is the most miserable of men. The cycle of scratching the itch, stimulating the need further to scratch the itch, is a trap – and a form of suffering. Suffering is sticky, and Freud’s economic problem of masochisms looms large and still has not been solved.

Doidge interweaves an account of a breakthrough psychoanalysis with a 50 plus year old gentleman with a narrative of Eric Kandel’s Nobel Prize winning research. Kandel and his team published on protein synthesis and the growth of neural connections needed to transform short- into long-term memory. While it is true that humans are vastly more complicated than the mollusks in Kandel’s study, the protein synthesis is not.

Thus, another neural mechanism is identified by which Talk Therapy changes your brain. Mark Solms – founding neuropsychoanalyst – and Oliver Turnbull translate Freud’s celebrated statement “where id was ego shall be” into neural science: “The aim of the talking cure […] from the neurobiological point of view [is] to extend the functional sphere of the influence of the prefrontal loves” (p. 233).

Even if we are skirting close to the edges of neuro-hype here, it is an indisputable factoid that Freud, the neurologist, draws a picture of a neuronal synapse in 1895 (p. 233). At the time, such a diagram was a completely imaginative and speculative hypothesis. Impressive. Freud also credibly anticipates Hebb’s law (“neurons that fire together wire together”), but then again, in this case, so did David Hume (in 1731) with his principle of association.

Meanwhile, back to the psychoanalysis with the 50-something gentleman who has suffered from a smoldering, low order depression for much of his life. Due to age, this is not considered a promising case. But that was prior to the emerging understanding of plasticity.

This provides Doidge with the opportunity to do some riffing, if not free associating, of his own about trauma, Spitz’s hospitalism, and psychopharmacology. “Trauma in infancy appears to lead to a supersensitization – a plastic alteration – of the brain neurons that regulate glucocorticoids” (p. 241). “Depression, high stress, and childhood trauma all release glucocorticoids and kill cells in the hippocampus, leading to memory loss” (p. 241). The result? The depressed person cannot give a coherent account of his life.

The ground breadking work of Rene Spitz on hospitalism – of children confined to minimum care hospitals (anticipating the tragic results in the Rumanian orphanages after the fall of the USSR) – is invoked as evidence of the damage that can occur. When the early environment is sufficient to keep the baby alive biologically but lacks the human (empathic) responsiveness required to promote the emotional well-being of the whole person, the result is similar to acquired autism – an overwhelmed, emotionally stunted person, struggling to survive in what seems to the individual to be a strange and unfriendly milieu.

I summarize the lengthy course of hard work required to produce the result of Doidge’s successful psychoanalysis. The uncovering of older, neural pathway gets activated and reorganized in the process of sustained free association, dream work, and the conversation for possibility in the psychoanalytic “talking cure”. Through an elaborate and lengthy process of working through, the patient regains his humanity, his lifelong depression lifts, and he is able to enjoy his retirement.

So far neural plasticity has been a positive phenomenon and a much needed source of hope and inspiration to action. However, plasticity also has a dark side. For example, if one loses a limb due to an amputation, the brain takes over what amounts to the now available neuronal space on the neural map. One’s physical anatomy has changed, but the brain seems plastically committed to reusing the neural map of the body for other purposes.

The limb is no longer there, but it hurts, cramps, burns, itches, because the neural map has not been amputated. However, the patient suffers – sometimes substantially – because one cannot massage or scratch a limb that does not exist. Yet the pain LIVEs in the neural system – and that makes it real.

Pain is the dark side of plasticity. Pain is highly useful and important for survival. It protects living creatures from dangers to life and limb such as fire or noxious substances. We have a painful experience and learn to avoid that which caused the pain.

Yet pain can take on a life of its own. Anticipating pain can itself be painful. Once pain is learned it is almost literally burned into the neurons and it takes considerable work (and ingenuity) to unlearn – to extinguish – the pain.

“Our pain maps get damaged and fire incessant false alarms” (p. 180). V. S. Ramachandran has performed remarkable work with understanding that most recalcitrant of phenomena, phantom limb pain. Ramachandran’s is deservedly famous for many reasons. But his simple innovation of the mirror box really requires an illustration. It is literally done with a mirror.

Illustrating mirror box therapy with an intact limb being reflected so as to create the appearance that the amputated limb is present: the individual experiences the presence of his missing limb

The subject with the missing hand is presented with a reflected image of the good, intact hand, which in reflection looks just like the missing hand. The subject experiences the limb as being a part of his body. (That in itself is a remarkable effect – the neural “socket” is still there.) In effect, the individual gets the hand back as something he owns. He is able to experience closing his missing hand by closing the good hand. This relieves cramps and stiffness.

In other experiments, the lights are turned off and various areas of the body are touched. The area that was once the [now missing] hand is used to map sensations on another area of the body, for example, one’s face. Scratching an itch on the phantom limb by scratching just the right spot on one’s face becomes possible because the neural map of the missing limb has been taken over and is now being used to map a different part of the anatomy

Doidge ends with a flourish:

“V. S. Ramachandra, the neurological illusionist, had become the first physician to perform a seemingly impossible operation: the successful amputation of a phantom limb” (p. 187). He did this by changing the brain – in effect deconditioning (deleting) the representation of the phantom limb from the brain. Thus, the promise and paradox of plasticity.